This invention relates to gas-cushion vehicles, that is to say, to vehicles for travelling over a surface and which, in operation, are supported above that surface, at least in part, by a cushion of pressurised gas, for example, air formed and contained between the vehicle body and the surface.
When a gas-cushion vehicle travels over an undulating surface such as rough water or ground, it experiences changes in volume and gas flow and thereby dynamic variations in the pressure of the vehicle-supporting cushion. These variations, unless reduced, result in the application of undesirable forces to the vehicle.